Small pump

ABSTRACT

Improvement in a small pump having the usual impeller, shaft, motor and housing characterized by a plurality of elongate housing sections that conformingly fit together laterally in an assembled condition to form the housing. The improved pump has a clamp ring serving as a portion of a means for joining and holding the housing sections together in the assembled condition; and a shroud for covering the motor for protection against droplets of spray. Also disclosed are specific structural features; such as, leg portions on the shroud for immobilizing the motor against movement longitudinally of the housing, flared end walls of the housing sections for effecting better clamping action, use of an adhesive means for joining edges of the housing sections together, and a separable base and impeller to facilitate assembly.

United States Patent [1 1 Aller 51 Sept. 24, 1974 SMALL PUMP T. Dwight Aller, Dallas, Tex.

Hydrometals, Inc., Dallas, Tex.

May 31, 1973 Inventor:

Assignee:

Filed:

Appl. No.:

US. Cl. 417/424 Int. Cl. F04b 17/00 Field of Search 417/424 References Cited UNITED STATES PATENTS Lotspih Timmons et al. Bunch 417/424 Primary Examiner-C. J. Husar Attorney, Agent, or Firm-Wofford, Felsman, Fails & Zobal [5 7] ABSTRACT Improvement in a small pump having the usual impeller, shaft, motor and housing characterized by a plurality of elongate housing sections that conformingly fit together laterally in an assembled condition to form the housing, The improved pump has a clamp ring serving as a portion of a means for joining and holding the housing sections together in the assembled condition; and a shroud for covering the motor for protection against droplets of spray. Also disclosed are specific structural features; such as, leg portions on the shroud for immobilizing the motor against movement longitudinally of the housing, flared end walls of the housing sections for effecting better clamping action, use of an adhesive means for joining edges of the housing sections together, and a separable base and impeller to facilitate assembly.

11 Claims, 6 Drawing Figures SMALL PUMP BACKGROUND OF THE INVENTION these pumps and motors have been relatively large and expensive for use in small campers or the like. Moreover, most such motors and pumps have required 110 volts for proper operation. One of the primary reasons for the expense of such motors has been the necessity to use corrosion resistant materials in both the housing and the pump and motor components, yet still have adequate structural strength. I-Ieretofore, the housings that have been employed have used a structure in which the motor and shaft could be inserted longitudinally through pre-formed integral housing. Infrequently, the housings have been disassemblable vertically with a coupling or the like on the shaft connecting the pump with the impeller, where the impeller was inserted in a preassembled impeller cavity. None of the prior art approaches have succeeded in reducing the cost of such small pumps as low as desirable. Moreover, difficulties were frequently obtained in effecting proper alignment and with retaining a motor and impeller in place against longitudinal movement to prevent subsequent binding of the impeller or motor against their housings.

Attempts to use low cost, low strength plastics in the pump housings has not been entirely successful because of the small diameter housings frequently would warp under the heat of an inactive cooler in the sun, or would cold flow under the stress of operating conditions.

Accordingly, it is an object of this invention to provide a small pump that obviates the disadvantages of the prior art structure and materials, yet provide a pump that is economical.

Another object of this invention is to provide a small, economical pump that is specifically adapted for evaporative coolers in campers or the like and that attains the object delineated hereinbefore.

These and other objects will become apparent from the descriptive matter hereinafter, particularly when taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of one embodiment of this invention.

FIG. 2 is an exploded view of the embodiment of FIG. 1.

FIG. 3 is a top view of the clamp ring of the embodiment of FIG. 2.

FIG. 4 is a side elevational view of the embodiment of FIG. 2 with the housing sections assembled together and the clamp ring ready to be moved upwardly thereabout.

FIG. 5 is a partial cross sectional view of the embodiment of FIG. 4.

FIG. 6 is a partial cross sectional view of the embodiment of FIG. 1 showing the clamp ring and shroud in place.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, the pump 11 is designed to sit in the bottom of an evaporative cooler for a camper or the like or be suspended from a clamp ring 21. The pump includes an impeller 13, a shaft 15, a motor 17 and a housing 19. The housing 19 comprises a plurality of elongate housing sections that conformingly fit together horizontally about the shaft 15 and impeller 13 and at least a portion of the motor 17. A clamping means that includes clamp ring 21 is provided for joining or holding together the housing sections in their assembled condition illustrated in FIG. 1. A shroud means, such as shroud 23, is provided for covering the motor 17 for protection against the water that is sprayed onto the sides of the evaporative cooler.

The impeller 13 may comprise any of the conventionally employed impellers. For example, it may be curved or straight and may be formed from any corrosion resistant material, such as brass or thermosetting or thermoplastic plastic materials. I have found it advantageous to make the impeller 13 from a thermoplastic material,

such as nylon or acrylonitrile butadiene stryene copolymer (ABS). As illustrated, the impeller 13 has an upwardly protruding cylindrical portion 25 that has a keyway 27 to facilitate insertion into a tubular lower end of the shaft 15 to facilitate assembly.

The shaft 15 may comprise any of the conventional type shafts carrying an impeller. Preferably, the shaft 15 is also formed of corrosion resistant material, such as the copper alloys or plastic. As illustrated, the shaft 15 comprises a cylindrical brass tube that is coupled to the shaft 29 of the motor 17 by plastic coupling 31. Any of the conventional couplings may be employed that will effect and maintain alignment of the shaft 15 with the shaft 29 of motor 17.

The motor 17 is drivingly connected with the shaft by the indicated coupling 31. Any suitable motor may be employed. The motor 17 is connected with a source of power. As illustrated, the motor 17 has conventional brushes and contacts, the brushes being located in cap 33. Since the brushes are of conventional construction, it would serve no purpose to have a detailed description of them. It is sufficient to note that they are connected by way of conductor strips 35 with the respective wires 37 and 39 that are in turn connected to respective terminals (not shown). In the illustrated embodiment, the motor 17 operates on l2 volt direct current (DC), so as to be operated directly off of the current of the vehicle battery, without requiring an alternator or vibrator: transformer combination to obtain volts alternating or pulsating current. As illustrated, the motor 17, shaft 15 and impeller 13 are maintained in vertical alignment by housing 19.

The housing 19 is formed of a plurality of elongate housing sections 41 and 43 that are conformingly fitted together laterally in an assembled condition, as illustrated in FIG. 1. Specifically, the housing sections fit together laterally about the shaft 15, the impeller 13 and at least the lower portion of the motor 17 to form the housing. When the housing is formed, it defines the motor cavity 45, the shaft cavity 47 and the impeller cavity 49. As can be seen clearly in FIG. 2, the housing sections may be joined together to form an aperture 51 that will serve as the inlet port, or a portion of the inlet to the impeller cavity 49. Peripherally elongate second apertures 53 are adapted to be submerged below the upper surface of the water in the evaporative coolers. The apertures 53 facilitate running of the water into the aperture 51 and, thence, into the impeller cavity 49 to be pumped, or recirculated, back over the filter pads (not shown) that cool the air. The housing sections 41 and 43 are joined at their lateral edges 56. They form a discharge conduit 55 by joining the two halves 55A and 55B. conventionally, a hose that is connected with a distribution system (not shown) is slipped onto the upper end 57 to recirculate the water.

As can be seen, the housing formed of the plurality of housing sections 41 and 43 has diametral dimensions that are large with respect to the diametral dimensions of the shaft 15. Consequently, the housing sections may be formed of a relatively low strength material, such as plastic, without suffering the disadvantages of the prior art housings. Expressed otherwise, the housing of the pump 11 is subjected to low unit stress because there is a relatively large quantity of material spaced over relatively large lateral dimensions to take the forces due to pumping, and the like. For this reason, the housing may be made of economical corrosion resistant material, such as plastic; instead of requiring more expensive corrosion resistant metallic alloys. Of course, the metallic alloys may be employed if desired. I have found it advantageous, however, to employ plastic. In fact, even the economical thermosetting plastic materials may be employed, as well as the more expensive and more easily worked with thermoplastic plastics. Specifically, the housing may be formed of ABS, or nylon; but it may also be formed of more economical plastic materials; such as phenol-formaldehyde copolymer, ureaformaldehyde copolymer, polyethylene, polypropylene, or polystyrene. I have found that the high-impact polystyrene plastic forms a particularly satisfactory and economical material from which to make the housing sections 41 and 43.

The conformingly fitting edges 56 of the housing sections 41 and 43 are bonded together by any suitable means. For example, they may be welded together by heating, or by suitable adhesive means. By adhesive means is meant any of the conventional adhesive materials; such as, glue, epoxy resins, or the so-called welding solvents. As is known, when heat is employed, the plastics are fused and joined together and allowed to re-solidify. With the glue or epoxy resin, the adhesive material is joined to the respective edges and then joined together. With the so-called welding solvents; a solvent, such as ethylene dichloride, is employed to partially dissolve a surface layer of the respective edges and then to allow fusing together of the edges in combination with the solvent action.

As illustrated, a separate base 59 is provided to facilitate assembly. Separate base 59 is adapted to conformingly receive the housing sections 41 and 43 in their assembled condition. Specifically, the housing sections 41 and 43 have a downwardly extending tab 61 on each side that fits within slots 63 on the base 59 to securely clamp the base to the housing sections upon relative rotation. The upper surface 65 of the base 59 is shaped to confirmingly receive the planar ends 67 of the housing sections 41 and 43. The upper surface 65 also forms the bottom of the impeller cavity 49 in the illustrated embodiment. The base 59 is adapted to sit on a planar bottom of a water reservoir in an evaporative coller in the illustrated embodiment.

Each edge 56 of each of the housing sections 41 and 43 has a longitudinally extending recess 71 adjacent its motor cavity 45 portion. Thus, when the housing sections 41 and 43 are joined together, the respective recesses 71 form a slot 73, FIG. 1, at the junction of each of the edges 56. Thus, the slots 73 are spaced about the motor cavity 45 in the assembled condition.

In assembly, the clamp ring 21 ordinarily will be moved longitudinally downwardly of the housing sections 41 and 43 before insertion of the motor 17 and shaft 15 from the top and insertion of the impeller 13 and the base 59 from the bottom. Thereafter, the motor 17 and shaft 15 are inserted and the impeller 13 emplaced on the shaft and the base 59 emplaced, as illustrated in FIG. 4. As can be seen in FIGS. 5 and 6, the camp ring 21 may be moved upwardly about the walls 75 of the upper end of the respective housing sections 41 and 43 to clamp the motor 17 in its motor cavity 45. The lower end of the motor cavity 45 has a shoulder 77 to prevent downward movement of the motor 17. The walls 75 have a thickness T at their outermost portion that is slightly greater than the thickness T on their inner portion such that, when the clamp ring 21 is moved upwardly, the upper ends of the walls 75 clamp the motor 17 to resist displacement longitudinally upwardly or downwardly.

As illustrated, the clamp ring 21 has gussets 79 and has apertures 81 to facilitate fastening it in place in the evaporative cooler. The gussets 79 provide adequate structural strength such that the clamp ring 21 could sustain the pump 11 in the event the base were broken or the like. As can be seen in FIG. 3, the clamp ring 21 has a large aperture 83 that may be employed for any one of several purposes. For example, it may be employed to pass the hose through to prevent its becoming engaged with the pulley or the squirrel cage blower in I the evaporative cooler. Alternatively, it may be employed for passing of electrical connectors or the like. The clamp ring 21 has interiorly protruding keys 85, FIG. 2, for engaging in the slots 73, FIG. 1, and preventing rotation of the clamp ring 21. Ordinarily, the bottom edge 87 of the clamp ring 21 will be bonded to the housing by the above-described procedure, such as smearing of the welding solvent at the juncture of the bottom edge 87 and the respective housing sections 41 and 43.

The cap 33, with its brushes, is emplaced about the top of the shaft of the motor and the contacts of the motor 17. The shroud 23 is emplaced over the cap 33. In addition to protecting the motor 17 from the fine droplets of water that may be dropped thereonto, the shroud 23 has leg portions 89 for preventing rotation of the shroud 23 and for immobilizing the motor 17 against longitudinal, or vertical, motion. As can be seen in FIG. 2, the cap 33 and the shroud 23 have similar ellipsoidal-type structure such that preventing rotation of one also prevents rotation of the other. As can be seen in FIG. 4, the leg portions 89 slide downwardly into the slots 73 for preventing rotation of the shroud 23. As illustrated in FIGS. 2 and 6, the leg portions 89 have respective shoulders 91 near their depending ends 93. The shoulders 91 are adapted to engage the interior edges of the clamp ring 21. As illustrated, the interior edges are formed by an interior edge 95 of the key 85. The key protrudes interiorly less than the total thickness of the walls 75 in order that the lower, or depending, end 93 and the shoulder 91 can slip between the key 85 and the motor housing, yet spring outwardly to engage the shoulder 91 with the interior edge 95. To facilitate passage of the lower end 93 past the key 85, an inclined surface 97 is provided. Preferably, the clamp ring 21 and the shroud 23 are emplaced on the pump 11 together so as to effect exact engagement of the shoulder 91 with the interior edge 95 before the clamp ring is bonded to the housing. In this way an exact fit is obtained with the motor 17 and impeller 13 correctly positioned.

The shroud 23 may be formed of any corrosion resistant material such as the corrosion resistant metallic alloys, or the plastic materials delineated hereinbefore. If the plastic materials are employed, it is preferable that they have sufficient flexure to do the job delineated hereinbefore, particularly for the leg portions 89. Consequently, the thermoplastic materials are preferably employed. 1 have found that polyethylene is a preferred material for forming the shroud 23.

In operation, the edges 56 of the plurality of housing sections 41 and 43 are bonded together and a clamp ring 21 slipped downwardly over the top of the resulting formed housing. The motor 17 and shaft are emplaced from the top. The impeller 13 is emplaced onto the shaft 15 from the bottom. The base 59 is then fixed to the bottom planar ends 67 of the fitted together housing sections 41 and 43 by inserting tabs 61 into slots 63 and rotating to securely clamp. The clamp ring 21 is slid upwardly to clamp the motor 17 in its motor cavity 45. The cap 33 is emplaced and the shroud 23 emplaced over the cap 33 with leg portions 89 in slots 73, as indicated hereinbefore. When the shroud 23 has been moved downwardly such that the shoulders 91 on leg portions 89 exactly engage the interior edge 95 of the key 85 of the clamp ring 21, the desired assembly will have been effected and the clamp ring is bonded at this height, as illustrated in FIG. 6. The pump 11 is then emplaced in the evaporative cooler, as by a bolt or screw through the aperture 81 of the clamp ring 21. The motor 17 is connected with suitable electrical contacts by way of conductors, or wires, 37 and 39. The distribution hose is connected with the upper end 57 of the discharge conduit 55 and connected with the distribution system for distributing the water over the filter pads. Thereafter, the pump 11 is turned on to circulate the water and cool the air being circulated past the filter pads.

From the foregoing, it can be seen that the clamp ring 21 and the adhesive means for bonding together the edges 56 combine to form a clamping means for joining and holding together the housing sections in their assembled condition.

While a separate base has been described hereinbefore, this invention encompasses the use of a plurality of housing sections that also include respective portions of the base such that the base is integrally formed when the housing sections are joined together.

While pumping of water for evaporative coolers has been described hereinbefore, thev economical pump 11 may be employed to pump any other liquid. Moreover, the motor may be adapted for use with any power source, such as a conventional l 10 volt alternating current source. a

From the foregoing, it can be seen that this invention provides the objects delineated hereinbefore. In particular, it provides an economical pump that can be formed of low cost, corrosion resistant material; yet obviate the deficiencies of the prior art type pumps. Specifically, the improved housing formed of the plurality of housing sections 41 and 43 that fit together laterally allows economical assembly. Moreover, because of the relatively large diametral dimensions of the resulting housing, it is not subject to stress concentrations as were the prior art pump housings and may be made of relatively low strength material, such as plastic. The specific combinations of the delineated structure allows significant market penetration in this area where economy and reliability are very significant.

Although this invention has been described with a certain degree of particularity, it is understood that the present disclosure is made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of this invention.

What is claimed is:

1. In a small pump adapted for pumping a liquid and including:

a. an impeller;

b. a shaft carrying said impeller;

c. a motor drivingly connected with said shaft and connected with a source of power; and

d. a housing including a base defining an impeller cavity with inlet and discharge ports;

the improvement comprising e. a plurality of elongate housing sections having side edges extending longitudinally of said housing that conformingly fit together laterally in an assembled condition about said shaft and impeller and at least a portion of said motor to form said housing and to define a motor cavity; a shaft cavity; and an inlet to, a discharge conduit from, and at least a portion of said impeller cavity;

f. clamping means for joining and holding said housing sections together in said assembled condition.

2. The pump of claim 1 wherein said clamping means comprises an adhesive means for joining the lateral edges of said housing section; said adhesive means being disposed intermediate the conformingly fitting edges of said plurality of housing sections; and a clamp ring that is initially slidable longitudinally of said housing section toward said motor cavity for clamping said housing sections about said motor.

3. The pump of claim 2 wherein each said housing section has a wall portion defining a portion of said motor cavity and having an outwardly extending flare in which its outermost thickness T is greater than its innermost thickness T for effecting a better clamping action when said clamp ring is slid upwardly into said assembled condition.

4. The pump of claim 2 wherein said clamp ring has laterally extending means for mounting said pump so it will take suction from a reservoir of said liquid.

5. The pump of claim 2 wherein there is provided shroud means for covering said motor for protection against said liquid in any form; said shroud means having means for engaging said housing in said assembled condition.

6. The pump of claim 5 wherein each edge of each said housing section has a longitudinally extending recess adjacent its motor cavity region so as to define a plurality of slots spaced about said motor cavity in said assembled condition and said shroud means has depending leg portions adapted to slide downwardly of said slots for retaining said shroud means in place.

7. The pump of claim 6 wherein said clamp ring has interiorly protruding key means for aligning with said slots and preventing rotation of said clamp ring and said clamp ring is adhered to said housing sections after assembly.

8. The pump of claim 6 wherein said clamp ring has a concentrically interior edge and said leg portions have respective shoulders near their depending ends adapted to engage said interior edges of said clamp ring for immobilizing said motor against longitudinal movement.

9. The pump of claim 1 wherein a separate base is provided to facilitate assembly; said separate base being adapted to conformingly receive said housing sections in said assembled condition and to define the bottom portion of said impeller cavity.

10. The pump of claim 9 wherein said impeller is connectable to said shaft from the bottom so as to be emplaced after said housing sections are assembled and before said separate base is connected to said housing; and said separate base is adhered to said housing.

11. The pump of claim 1 wherein said plurality of elongate housing sections is two. 

1. In a small pump adapted for pumping a liquid and including: a. an impeller; b. a shaft carrying said impeller; c. a motor drivingly connected with said shaft and connected with a source of power; and d. a housing including a base defining an impeller cavity with inlet and discharge ports; the improvement comprising: e. a plurality of elongate housing sections having side edges extending longitudinallY of said housing that conformingly fit together laterally in an assembled condition about said shaft and impeller and at least a portion of said motor to form said housing and to define a motor cavity; a shaft cavity; and an inlet to, a discharge conduit from, and at least a portion of said impeller cavity; f. clamping means for joining and holding said housing sections together in said assembled condition.
 2. The pump of claim 1 wherein said clamping means comprises an adhesive means for joining the lateral edges of said housing section; said adhesive means being disposed intermediate the conformingly fitting edges of said plurality of housing sections; and a clamp ring that is initially slidable longitudinally of said housing section toward said motor cavity for clamping said housing sections about said motor.
 3. The pump of claim 2 wherein each said housing section has a wall portion defining a portion of said motor cavity and having an outwardly extending flare in which its outermost thickness T1 is greater than its innermost thickness T2 for effecting a better clamping action when said clamp ring is slid upwardly into said assembled condition.
 4. The pump of claim 2 wherein said clamp ring has laterally extending means for mounting said pump so it will take suction from a reservoir of said liquid.
 5. The pump of claim 2 wherein there is provided shroud means for covering said motor for protection against said liquid in any form; said shroud means having means for engaging said housing in said assembled condition.
 6. The pump of claim 5 wherein each edge of each said housing section has a longitudinally extending recess adjacent its motor cavity region so as to define a plurality of slots spaced about said motor cavity in said assembled condition and said shroud means has depending leg portions adapted to slide downwardly of said slots for retaining said shroud means in place.
 7. The pump of claim 6 wherein said clamp ring has interiorly protruding key means for aligning with said slots and preventing rotation of said clamp ring and said clamp ring is adhered to said housing sections after assembly.
 8. The pump of claim 6 wherein said clamp ring has a concentrically interior edge and said leg portions have respective shoulders near their depending ends adapted to engage said interior edges of said clamp ring for immobilizing said motor against longitudinal movement.
 9. The pump of claim 1 wherein a separate base is provided to facilitate assembly; said separate base being adapted to conformingly receive said housing sections in said assembled condition and to define the bottom portion of said impeller cavity.
 10. The pump of claim 9 wherein said impeller is connectable to said shaft from the bottom so as to be emplaced after said housing sections are assembled and before said separate base is connected to said housing; and said separate base is adhered to said housing.
 11. The pump of claim 1 wherein said plurality of elongate housing sections is two. 